Carasobarbus luteus (Heckel, 1843),

Borkenhagen, Kai & Krupp, Friedhelm, 2013, Taxonomic revision of the genus Carasobarbus Karaman, 1971 (Actinopterygii, Cyprinidae), ZooKeys 339, pp. 1-53: 29-36

publication ID

http://dx.doi.org/10.3897/zookeys.339.4903

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http://treatment.plazi.org/id/45042280-2F92-D175-42C4-951DA963F58C

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scientific name

Carasobarbus luteus (Heckel, 1843)
status

 

Carasobarbus luteus (Heckel, 1843) 

Systomus luteus  Heckel 1843: 1161.

Systomus albus  Heckel 1843: 1163.

Systomus albus  var. alpina Heckel 1847: 257.

Barbus parieschanica  Wossughi et al. 1983: 34.

Material.

Type material. Nahr Quwayq basin. Paralectotypes of Systomus luteus  : NMW 54248, 1; NMW 54250:1-2, 2; NMW 54254:1-3, 3; SMF 6784, 1, Syria, Nahr Quwayq near Aleppo [36°12'10"N, 37°9'31"E], T. Kotschy, 17 May 1842.

Syntypes of Systomus albus  : NMW 53674-53677, 4; NMW 53680, 1; SMF 812, 1, Syria, Nahr Quwayq near Aleppo [36°12'10"N, 37°9'31"E], T. Kotschy, 18 May 1842.

Rūd-e Mand basin. Syntypes of Systomus albus alpina  : NMW 53678, 5; NMW 53679:1-2, 2; NMW 53681:1-2, 2, Iran, Rūdkhāneh-ye Qarah Āghāj near Shīrāz [29°31'3"N, 52°15'0"E], 2 Jan 1844.

Rūdkhāneh-ye Ḩelleh basin. Syntypes of Systomus albus alpina  : NMW 53682:1-2, 2, Iran, Daryācheh-ye Parīshān [29°31'7"N, 51°47'47"E].

Tigris-Euphrates system. Lectotype of Systomus luteus  (by present designation): NMW 54253:2, Iraq, Tigris near Mosul [36°20'6"N, 43°7'8"E], T Kotschy, 10 Apr 1843.

Paralectotypes of Systomus luteus  : NMW 54247:1-2, 2; NMW 54249, 1; NMW 54253:1, 1; NMW 54255:1-2, 2; NMW 80043, 2 same data as lectotype.

Syntype of Systomus albus  : NMW 91400, 1, Iraq, Tigris near Mosul [36°20'6"N, 43°7'8"E], 11 Apr 1843.

Unknown drainage system. Paralectotype of Systomus luteus  : NMW 10827, 1, Syria, “Damascus”, T. Kotschy, 1837.

Non-type material. Daryācheh-ye Mahārlū basin. CMNFI 79-0047, 1, Iran, source of Ab-e Paravan marshes 19.9 km from Shīrāz University [29°36'N, 52°32'E]. - FSJF 2232, 2, Iran, Pirbano spring about 10 km south of Shīrāz (29°31'8"N, 52°27'56"E), A. Abdoli and J. Freyhof, 21 Apr 2007. - ZM-CBSU 3439, 1; ZM-CBSU 3449, 1; ZM-CBSU uncatalogued, 1, Iran, Pol-e Berenji, southwest of Shīrāz [29°27'30"N, 52°32'0"E], H. R. Esmaeili et al. - CMNFI 79-0347, 1, Iran, Solţānābād marshes near Pol-e Berenji (29°27'30"N, 52°32'0"E).

Orontes basin. MNHN 1977-0255, 1, Syria, Orontes, Gruvel, 1929, only one of two specimen examined. - MNHN 1977-0257, 1, Syria, Orontes, Gruvel, 1930. - SMF 24341, 1, Syria, Orontes at Jisr ash Shughūr (35°48'N, 36°19'E), F. Krupp, 21 Mar 1979 (aberrant specimen).

Rūd-e Mand basin. CMNFI 79-0206, 1, Iran, Qanat 41 km from Estahbān on road to Kharāmeh (29°12'N, 53°40'E). - CMNFI 79-0160, 1, Iran, cement pool near spring along road to Neyrīz (29°9'N, 53°37'E). - ZM-CBSU 4934-4942, 9, Iran, Dareh Daarveshan between Rudbal and Simakan (28°39'10"N, 52°2'27"E), H. R. Esmaeili et al. - ZM-CBSU 101-103, 3; ZM-CBSU 110, 1; ZM-CBSU uncatalogued, 1, Iran, Rūdkhāneh-ye Sīmakān near Jahrom [28°30'0"N, 53°33'38"E], H. R. Esmaeili et al.

Rūdkhāneh-ye Ḩelleh basin. CMNFI 79-0026, 1, Iran, Rūdkhāneh-ye Shāhpūr near Shahr-e Tārīkhī-ye Neyshābūr (29°47'N, 51°35'E). - ZM-CBSU 5180-5190, 10; ZM-CBSU 5192, 1, Iran, Kāzerūn, Sarab Dokhtar [29°37'10"N, 51°39'15"E], H. R. Esmaeili et al. - ZM-CBSU 6508-6517, 10; ZM-CBSU 6574, 1; ZM-CBSU 6602-6607, 6; ZM-CBSU 6610, 1; ZM-CBSU 6614+6615+6617-6619, 5; ZM-CBSU uncatalogued, 12, Iran, Daryācheh-ye Parīshān [29°31'7"N, 51°47'47"E], H. R. Esmaeili et al. - CMNFI 79-0240, 2; CMNFI 79-0304, 3, Iran, Daryācheh-ye Parīshān (29°31'N, 51°50'E). - CMNFI 79-0125, 1, Iran, Rūdkhāneh-ye Dālakī near Dālakī (29°28'N, 51°21'E). - ZM-CBSU 2650-2651, 2; ZM-CBSU 2654-2655, 2, Iran, spring at Palangī Dādīn, near Kāzerūn, Rūdkhāneh-ye Dālakī [29°25'20"N, 51°43'54"E], H. R. Esmaeili et al.

Rūdkhāneh-ye Kol basin. ZM-CBSU 3219-3229, 11; ZM-CBSU 3252-3260, 9, Iran, Golabi spring north of Dārāb [28°47'15"N, 54°22'19"E], H. R. Esmaeili et al. - FSJF 2253, 6, Iran, Golabi spring 35 km north of Dārāb (28°47'15"N, 54°22'19"E), A. Abdoli and J. Freyhof, 21 Apr 2007. - CMNFI 79-0155, 1, Iran, spring at Gavanoo, east of Ḩasanābād [28°47'N, 54°22'E]. - CMNFI 79-0154, 2, Iran, Korsia vil lage on Dārāb-Fasā road (28°45'30"N, 54°24'0"E). - ZM-CBSU 5622-5626, 5, Iran, Tang-e Khūr near Lār [27°36'N, 54°17'E], H. R. Esmaeili et al.

Rūdkhāneh-ye Naband basin. CMNFI 79-0187, 10, Iran, stream and pools at Sarkhūn, Rūdkhāneh-ye Sarzeh (27°23'30"N, 56°26'0"E).

Tigris-Euphrates system. SMF 30208, 1, Turkey, Tigris at Diyarbakır (37°53'N, E40°14'), R. Kinzelbach, 1982. - SMF 30176, 11, Syria, Nahr al Khābūr at Ra’s al 'Ayn (36°51'N, 40°4'E), F. Krupp, 24-26 May 1989. - SMF 30186, 12, Syria, 'Ayn Sālūba and 'Ayn Hamza near Ra’s al 'Ayn (36°51'N, 40°4'E), F. Krupp, 3 Oct 1988. - SMF 30200, 2, Syria, 'Ayn Sālūba at Ra’s al 'Ayn (36°51'N, 40°4'E), F. Krupp, 3 Oct 1988. - SMF 30190, 7, Syria, Nahr al Khābūr 2 km East of Tall Junaydīyah (36°44'N, 40°6'E), F. Krupp, 26 May 1989. - SMF 30197, 2, Syria, Nahr al Khābūr 2 km East of Tall Junaydīyah (36°44'N, 40°6'E), F. Krupp, 5 Oct 1988. - SMF 30179, 3, Syria, Nahr al Khābūr at Tall ʿAtaš (36°42'N, 40°11'E), F. Krupp, 26 May 1989. - SMF 30188, 3, Syria, Nahr al Khābūr at Tall ʿAtaš (36°42'N, 40°11'E), F. Krupp, 6 Oct 1988. - SMF 31317, 1; SMF 33139, 7, Syria, Nahr al Khābūr at Tall Tamr (36°39'7"N, 40°21'51"E), N. Alwan et al., 29 Oct 2008. - SMF 30199, 1, Syria, Nahr al Khābūr at Tall Naşrī (36°37'N, 40°23'E), F. Krupp, 6-7 Oct 1988. - SMF 30178, 1; SMF 30202, 10, Syria, Nahr al Khābūr near Tall Bāz (36°35'N, 40°27'E), F. Krupp, 7 Oct 1988. - SMF 30184, 1; SMF 30193, 3, Syria, Nahr al Khābūr at Tall Bāz (36°35'N, 40°27'E), F. Krupp, 26 May 1989. - SMF 30181, 1; SMF 30192, 3, Syria, Nahr al Khābūr at Tall Umm al Māʿaz (36°34'N, 40°35'E), F. Krupp, 27 May 1989. - SMF 30183, 3, Syria, Nahr al Khābūr at Umm al-Māʿaz (36°34'N, 40°35'E), F. Krupp, 7 Oct 1988. - SMF 30182, 2, Syria, Nahr al Khābūr at Al Ḩasakah (36°30'N, 40°44'E), F. Krupp, 27 May 1989. - SMF 30195, 1, Syria, Nahr al Khābūr at Al Ḩasakah (36°30'N, 40°44'E), F. Krupp, 7 Oct 1988. - SMF 30185, 1; SMF 30213, 6, Syria, Nahr al Khābūr and Wādī Furātī at Tall Tayyiǧ (36°26'N, 40°52'E), F. Krupp, 8 Oct 1988. - SMF 30189, 4, Syria, Nahr al Khābūr at Baḩrat Khātūnīyah (36°24'N, 41°13'E), F. Krupp, 23-24 May 1989. - SMF 30214, 5, Syria, Nahr al Khābūr at Tall Budayrī (36°24'N, 40°49'E), F. Krupp, 26 Sep– 8 Oct 1988. - SMF 30206, 7, Syria, Nahr al Khābūr at Tall Budayrī (36°24'N, 40°52'E), F. Krupp, 2-4 Nov 1986. - SMF 30177, 3, Syria, Nahr al Khābūr at Nahāb (36°23'N, 40°50'E), F. Krupp, 28 Sep– 8 Oct 1988. - SMF 30201, 23, Syria, Nahr al Khābūr at 'Ayn Ţābān (36°22'N, 40°50'E), F. Krupp, 28 Sep 1988. - SMF 30191, 2, Syria, Nahr al Khābūr at mouth of Wādī ar Raml (36°15'N, 40°48'E), F. Krupp, 8 Oct 1988. - SMF 30196, 1, Syria, Nahr al Khābūr at Umm Rukaybah (36°8'N, 40°42'E), F. Krupp, 8 Oct 1988. - SMF 30194, 3, Syria, Nahr al Khābūr at Ash Shaddādah (36°4'N, 40°44'E), F. Krupp, 9 Oct 1988. - SMF 31316, 1; SMF 33138, 2, Syria, Nahr al Khābūr at Ash Shaddādah (36°3'46"N, 40°44'30"E), N. Alwan et al., 28 Oct 2008. - SMF 33152, 6, Syria, Jisr Shānīn (36°3'4"N, 39°5'10"E), F. Krupp and W. Schneider, 19 Aug 1980. - SMF 31308, 1, Syria, Mamlaḩat al Jabbūl (36°3'36"N, 37°33'1"E), N. Hamidan, 23 Jun 2008. - SMF 28707, 18, Syria, Euphrates down stream Buḩayratt al Asad (35°51'48"N, 39°0'34"E), R. Beck, Jun 1998. - SMF 30198, 2, Syria, Nahr al Khābūr at Tall ash Shaykh Ḩamad (35°37'N, 40°45'E), F. Krupp, 21 Sep– 14 Oct 1988. - SMF 30204, 1; SMF 30205, 4, Syria, Nahr al Khābūr at Tall ash Shaykh Ḩamad (35°37'N, 40°45'E), F. Krupp, 20 Oct– 9 Nov 1986. - SMF 33140, 1; SMF 33141, 37, Syria, Euphrates at Harmūshīyah (35°35'52"N, 39°51'25"E), N. Alwan et al., 31 Oct 2008. - SMF 30203, 2, Syria, Nahr al Khābūr 8 km South of Tall ash Shaykh Ḩamad (35°33'N, 40°43'E), F. Krupp, 24 Oct 1986. - SMF 28737, 5, Syria, Euphrates between Ḩalabīyah-Zalābīyah and Dayr az Zawr, R. Beck, Jun 1998. - SMF 28630, 3, Syria, Euphrates upstream Dayr az Zawr (35°31'N, 39°54'E), R. Beck, 23 May 1998. - SMF 28674, 41, Syria, Euphrates upstream Dayr az Zawr [35°31'N, 39°54'E], R. Beck, 30 May 1998. - SMF 33153, 1, Syria, Nahr al Khābūr at Aş Şuwar (35°30'N, 40°38'E), F. Krupp, 15 Mar 1979. - SMF 31315, 1; SMF 33137, 1, Syria, Nahr al Khābūr at Ghawat (35°28'51"N, 40°39'54"E), N. Alwan et al., 28 Oct 2008. - SMF 30187, 2, Syria, Nahr al Khābūr near Ḩarījīyah (35°27'N, 40°38'E), F. Krupp, 10 Oct 1988. - SMF 30180, 5, Syria, Nahr al Khābūr at Mashikh (35°14'N, 40°31'E), F. Krupp, 10 Oct 1988. - SMF 28663, 6, Syria, Euphrates at Qal‘at aş Şāliḩīyah (Dura Europos) [34°45'0"N, 40°43'30"E], R. Beck, 28 May 1998. - SMF 28758, 2, Syria, Euphrates at Abū Kamāl at mouth of Wādī Ratqah [34°26'45"N, 40°56'0"E], R. Beck, 9 Jul 1998. - NMW 93019:1-2, 2, Iraq, Tigris at Baghdād [33°20'26"N, 44°24'3"E], V. Pietschmann, Aug 1910. - SMF 33127, 4, Iran, Rūdkhāneh-ye Bālārūd (32°35'19"N, 48°17'11"E), N. Alwan et al., 3 Mar 2008. - BMNH 1980.8.28:6, 1, Iran, Rūdkhāneh-ye Dez at Dezfūl [32°25'N, 48°13'E]. - SMF 33125, 1, Iran, Rūdkhāneh-ye Dez at Dezfūl (32°22'40"N, 48°22'58"E), N. Alwan et al., 2 Mar 2008. - SMF 33121, 5, Iran, Rūdkhāneh-ye Dez at Dezfūl (32°21'49"N, 48°21'28"E), K. Borkenhagen et al., 3 Nov 2006. - SMF 17303, 1, Iraq, Hawr al Ḩammār (30°50'N, 47°10'E), L. A. J. Al-Hassan, 1986. - SMF 30211, 1, Iraq, 'Ayn Zālah 50 km west of Mosul, Z. Rahemo, 1990.

Unknown drainage system. SMF 33120, 2, Syria, fish market in Damascus (reported to be from Buḩayratt Ar Rastan [34°56'N, 36°44'E] in Orontes drainage), F. Krupp. - CMNFI 79-0687, 4, Iran, Shīrāz bazar (probably from Rūd-e Mand basin or Daryācheh-ye Mahārlū basin).

The lectotype (NMW 54253:2) is a specimen of 211 mm SL, collected in the Tigris near Mosul on 10 Apr 1843 by T. Kotschy (Fig. 23). It has four unbranched and 10 branched rays in the dorsal fin, three unbranched and six branched rays in the anal fin, 27 scales in the lateral line and one pair of barbels. A bigger specimen (216 mm SL) from the same lot (NMW 54253:1) was not selected as lectotype, because it is atypical in having 11 branched rays in the dorsal fin and two pairs of barbels. The designation of a lectotype became necessary to fix the type locality of Systomus luteus  (see Discussion).

Diagnosis.

One pair of barbels; 25 to 33 scales in the lateral line, and typically 12 scales around the least circumference of the caudal peduncle; last unbranched ray of the dorsal fin about as long as the head or slightly shorter.

Description.

Specimens from Rūdkhāneh-ye Naband basin were excluded from this species description (see below).

The dorsal profile is convex up to the origin of the dorsal fin and a nuchal hump is present in specimens longer than about 100 mm SL. This species has a high back and caudal peduncle (Figs 23, 24). The ventral profile of the head is convex, its dorsal pro file is almost straight to convex and has a hump near the nostrils in juvenile specimens. The mouth is sub-terminal. The barbels are short and stout. The maximum body depth is usually greater than the head length (Fig. 12). Usually one pair of barbels is present, but about 10 % of the specimens have two pairs of barbels (Table 2). The eyes are at the back of the anterior half of the head. They are big and slightly protuberant. The morphometric characters are summarised in Table 1.

The dorsal fin usually has four unbranched and eight to 11 branched rays (Table 3). In specimens from the Tigris-Euphrates drainage system the last unbranched ray of the dorsal fin is strong with only the tip being flexible and it is about as long as the head. It is shorter and less ossified in Iranian populations (Fig. 4). The anal fin usually has three unbranched rays and five to seven branched rays (Table 4).

There are 25 to 33 scales in the lateral line (Table 5), 3.5 to 6 scales above the lateral line (Table 6), 3 to 5.5 scales below the lateral line (Table 7) and 10 to 13 scales around the least circumference of the caudal peduncle (Table 8). The scales are shown in Fig. 5.

The pharyngeal teeth count is 2.3.5-5.3.2 in 26 specimens, 2.3.4-5.3.2 in two specimens, 2.3.5-4.3.2 in one specimen, 2.3.5-5.3.3 in one specimen, 1.3.5-5.3.2 in one specimen, 2.3.5- in one specimen and 2.3.4- in one specimen. The pharyngeal teeth are hooked at their tips (Fig. 6).

Live specimens are silvery to olive and sometimes have yellowish fins (Fig. 24). Ethanol-preserved specimens are light yellowish brown to grey. In most cases the back is darker than the rest of the body. Some of the lighter coloured specimens have a salmon hue, others are silvery. The fins are yellowish brown to grey. Juveniles have a dark spot on the sides of the caudal peduncle.

Carasobarbus luteus  from Ḩelleh, Kol, Mahārlū and Mand populations: The last unbranched ray of the dorsal fin is shorter and less well ossified. It is pronouncedly shorter than the head (Fig. 4). The mouth is wider and the body is not as high-backed as in specimens from the Tigris-Euphrates system (Fig. 12).

Carasobarbus luteus  from Rūdkhāneh-ye Naband basin: In this population all specimens examined had two pairs of barbels (Table 2). The anterior pair is longer than in specimens from Tigris-Euphrates system with two pairs. The last unbranched ray in the dorsal fin is considerably shorter than the head (Fig. 4) and comparatively weak. Compared with specimens from Tigris-Euphrates system, the dorsal and ventral fins tend to be slightly further away from the head. The head is longer and the body not as high backed as in specimens from Tigris-Euphrates system (Fig. 12). The general body shape (Fig. 25) resembles that of Carasobarbus apoensis  and Carasobarbus canis  . Some of the gill rakers are y-shaped in the largest specimen examined.

Carasobarbus luteus  , except the population from Rūdkhāneh-ye Naband, differs from all congeners, except Carasobarbus apoensis  , in having one instead of two pairs of barbels. It differs from Carasobarbus apoensis  , Carasobarbus canis  , Carasobarbus chantrei  , Carasobarbus fritschii  , Carasobarbus harterti  and Carasobarbus kosswigi  in modally having 28 scales in the lateral line vs. 30, 32, 34, 34, 34 and 33 respectively. It differs from Carasobarbus kosswigi  and Carasobarbus sublimus  in having a crescent-shaped lower lip without median lobe vs. a spatulate lower lip with median lobe and from Carasobarbus exulatus  , Carasobarbus fritschii  and Carasobarbus harterti  in modally having 10 rather than nine branched dorsal-fin rays. All populations, except the one from Rūdkhāneh-ye Naband differ from Carasobarbus apoensis  in having a shorter head and a higher back. The population from Rūdkhāneh-ye Naband is very similar to Carasobarbus apoensis  in body shape, but differs in having two as compared to one pair of barbels.

Distribution.

Carasobarbus luteus  has a much greater range than any of its congeners and its distribution area is fragmented, resulting in several isolated populations. It is widespread all over the Tigris-Euphrates drainage system, and occurs in the rivers of south-western Iran (Fig. 7). The Nahr al Quwayq population, from one of the sites of the type locality, is probably extirpated due to drought and pollution ( Krupp 1980, Krupp 1983b). There are only few, mostly older, records from the Orontes ( Krupp 1985c, Krupp 1987). During recent fieldwork Carasobarbus luteus  was not found there. Because Carasobarbus chantrei  is still widespread and abundant in many parts of the Orontes, it is unlikely that Carasobarbus luteus  disappeared due to habitat degradation. It might have been driven out by competition with Carasobarbus chantre  i or records were based on misidentifications or mislabelled specimens. One specimen (NMW 10827) is reported from Damascus. Because Carasobarbus luteus  does not occur in the Damascus basin and it is highly unlikely that it ever occurred there, the origin of this specimen is unclear.

Habitats and biology.

Carasobarbus luteus  is mainly herbivorous. It feeds on algae, aquatic plants, detritus and small invertebrates, the main feeding period is at noon, but food is also taken at night ( Naama and Muhsen 1986). The intestine is long ( Ali 1986). The maximum size is 38 cm total length and 750 g, but normally they are smaller than 35 cm and weight less than 500 g ( Ahmed 1982). They reach maturity at the age of one or two years and at a size of about 14 cm; the spawning period is June and July in the Tigris-Euphrates system, the eggs are spawned among reeds, roots or other aquatic vegetation and fecundity is high ( Al Hazzaa and Hussein 2003a).

This species can tolerate saline waters to some degree ( Al-Hassan and Muhsin 1986, Mohamed et al. 1993) and is of commercial importance due to its size and abundance ( Ahmed 1982, Barak and Mohamed 1983, Krupp and Schneider 2008).

There are attempts on aquaculture of this species. The stickiness of the eggs can be lowered by several chemical treatments for this purpose ( Al Hazzaa and Hussein 2003b). During spawning males get reddish brown in the anterior part of the body and greenish at the caudal peduncle while females are less colourful ( Al Hazzaa and Hussein 2003a). Males can produce series of sharp clicking noises which do not seem to be associated with aggressive behaviour ( Al Hazzaa and Hussein 2003a).

Larvae hatch at 64 degree-days in well oxygenated water and the eyes are still without pigments at this stage. The development is similar to that of other cyprinids ( Al Hazzaa and Hussein 2003a). Ahmed et al. (1984) studied the reproductive biology of Carasobarbus luteus  .

Conservation status. Carasobarbus luteus  is widespread and abundant in the Tigris-Euphrates system. Peripheral populations, like those in smaller Iranian rivers and the Nahr al Quwayq in Syria are more threatened or have already been extirpated (see above).

Discussion.

Carasobarbus luteus  was described as Systomus luteus  by Heckel (1843). Heckel (1843) listed Orontes, Tigris, Aleppo and Mosul as type localities. As all but one of the type specimens are either from the Tigris-Euphrates system or from the Nahr al Quwayq and Aleppo is located on the Nahr al Quwayq and not on the Orontes, Heckel may have confused these two rivers. One of the type specimens (NMW 10827) is from “Damascus” and can not be attributed to any of the relevant drainage systems. By designating NMW 54253:2 as lectotype we fix the Tigris near Mosul as type locality for Systomus luteus  . The same confusion exists for the type localities of Systomus albus  , which was also described from Tigris and Orontes in the same publication. A few years later Systomus albus  var. alpina was described from the Daryācheh-ye Parīshān ( Heckel 1847). These three taxa where later synomymised and placed in the genus Barbus  ( Günther 1868). Sauvage (1882, 1884) accepted Carasobarbus luteus  and Carasobarbus albus  as valid species and transferred them to the genus Barynotus  . Later, both species where synonymised again and transferred to the genus Barbus  , subgenus Puntius  ( Misra 1947) or the genus Puntius  ( Menon 1956). Ladiges (1960) synonymised both species under the name Barynotus albus  . Because Günther (1868) had previously selected luteus as the valid species name, he is to be considered the first revising author and Ladiges’ action is not valid. Kähsbauer (1963) lists the species under two different generic names: Barbus  (as Barbus luteus  ) and Systomus  (as Systomus albus  var. alpina). Karaman (1971) erected the new genus Carasobarbus  for this species. This met mixed acceptance. While some authors accepted the new taxonomic position (e.g. Wossughi 1978, Bianco and Banarescu 1982, Ahmed et al. 1984, Naama and Muhsen 1986), others did not embrace it (e.g. Banister and Clarke 1977, Krupp 1985a, c, Coad 1995, Coad 1996) until the revision by Ekmekçi and Banarescu (1998). Fowler (1976) placed Carasobarbus luteus  in the genus Barbellion  . Tsigenopoulos et al. (2010) used Barbus  subgenus Carasobarbus  . Barbus parieschanica  was described from Daryācheh-ye Parīshān ( Wossughi et al. 1983). In the same publication the species name is also spelled B. parschanica, but Barbus parieschanica  is probably the intended spelling ( Coad 1995). Coad (1995) as the first revising author fixed Barbus parieschanica  as the correct original spelling. Barbus parieschanica  is a synonym of Carasobarbus luteus  . The 'Catalog of Fishes’ lists RMNH 2463 as possible syntype of Systomus luteus  and RMNH 2464 of Systomus albus  var. alpina ( Eschmeyer 2011). We did not examine these specimens.

We do not think that the population at Rūdkhāneh-ye Naband should be elevated to specific rank, because the number of specimens available is too low. We provisionally consider it an atypical population of Carasobarbus luteus  that might have been affected by bottleneck effects and accelerated morphological change, due to the restricted size and extreme conditions (high salinity and temperature) of its habitat. It would be very interesting to collect more samples for morphological studies and molecular sequence analysis.

In spite of some morphometric differences, Carasobarbus luteus  populations of Tigris-Euphrates system and Iran belong to the same species ( Borkenhagen et al. 2011); specimens from Rūdkhāneh-ye Naband were not included in that study.

Carasobarbus luteus  and Carasobarbus apoensis  are closely related to each other (KB, unpublished data) and Carasobarbus apoensis  might be the ecologically specialised sister species of Carasobarbus luteus  , that is adapted to the environmental conditions of the wadi ecosystems of the Al Ḩijāz mountains.